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    <title>Document</title>
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<script>
console.log("坤坤帅" && "龙哥帅") //龙哥帅
console.log(0 && 1) //0
console.log(null && true) //null
console.log(true && NaN) //NaN
console.log(1 && 0 && 2) //0
console.log(1 && true && 2) //2


console.log("坤坤帅" || "龙哥帅") //坤坤帅
console.log(0 || 1) //1
console.log(null || true) //true
console.log(true || NaN) //true
console.log(1 || 0 || 2) //1
console.log(1 || true || 2) //1
console.log(0 || true || false) // true



console.log(2 && 1 + 2) // 3
console.log(0 && 2 + 2) // 2
console.log(NaN && 1 + 2) //NaN

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